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On my 335xi E92 I had a custom exhaust installed. The set is w/DP, straight pipes and 2 small mufflers. Needless to say the exhaust is TOO loud! (shocker) So here it goes. We installed 2 capped off resonators right before the mufflers to eliminate the drone. Worked somewhat but here is the overall problem.

Bottom line it's too loud at start up AND especially just driving around and town and more so at highway speeds. I want it QUIET now. WHAT ARE ITEMS I NEED TO ADDRESS??? Also, I got a custom tune which is great hence the DP. So...where do I start from here to eliminate this loud noise? Get rid of DP (catless btw). Completely change the mufflers in the rear to one big one? This whole project backfired since I never knew how loud this was going to be. I need help bigtime!! :bawling:
 

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Maybe you should give it some time before you make any additional changes. I know mine seemed pretty loud when I first added my catless downpipes, but now I love the sound. I will have to admit that it is still very loud at startup and I make sure my windows are rolled up in the mornings in the garage before I start it, but after about 15 seconds it settles down. Here is a bit of a Colorado analogy for you. Since marijuana is legal here, a lot of people have started making edibles instead of smoking it because it doesn't have the smell, etc. associated with marijuana. It would normally take a newby about 1/2 of a cookie to get pretty high, but you don't feel the full effect for about 3 hours. Some people don't feel enough in a half hour and eat a whole cookie and then another within 2 hours, and then by that time you have over done it and probably end up feeling sick and not enjoying it. I think in this case, you may have eaten two cookies right off the bat. Let it sink in for a few weeks and reevaluate it then. I know it took me a couple of months until I really enjoyed mine.
 

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The downpipes in my opinion didn't make the car much louder. It wasn't till I added my BMW PE exhaust that made it loud.
 

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The 335is already comes with a different exhaust than the 335i so I had plenty of sound when I made the change. I don't think it is the same as the PE that you can buy from BMW, but specific to the "is".
 

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Maybe you should give it some time before you make any additional changes. I know mine seemed pretty loud when I first added my catless downpipes, but now I love the sound. I will have to admit that it is still very loud at startup and I make sure my windows are rolled up in the mornings in the garage before I start it, but after about 15 seconds it settles down. Here is a bit of a Colorado analogy for you. Since marijuana is legal here, a lot of people have started making edibles instead of smoking it because it doesn't have the smell, etc. associated with marijuana. It would normally take a newby about 1/2 of a cookie to get pretty high, but you don't feel the full effect for about 3 hours. Some people don't feel enough in a half hour and eat a whole cookie and then another within 2 hours, and then by that time you have over done it and probably end up feeling sick and not enjoying it. I think in this case, you may have eaten two cookies right off the bat. Let it sink in for a few weeks and reevaluate it then. I know it took me a couple of months until I really enjoyed mine.
+1 mine is ridiculously loud on cold starts and around town it has a low hum, at first I hated it then after about a couple weeks i came to love it, especially the notes it hits when on full throttle. You're not used to the difference in sound yet and it does take some getting used to so I would recommend giving it a few days to adjust

Sent with my carrier pigeon
 

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Discussion Starter #6
Maybe you should give it some time before you make any additional changes. I know mine seemed pretty loud when I first added my catless downpipes, but now I love the sound. I will have to admit that it is still very loud at startup and I make sure my windows are rolled up in the mornings in the garage before I start it, but after about 15 seconds it settles down. Here is a bit of a Colorado analogy for you. Since marijuana is legal here, a lot of people have started making edibles instead of smoking it because it doesn't have the smell, etc. associated with marijuana. It would normally take a newby about 1/2 of a cookie to get pretty high, but you don't feel the full effect for about 3 hours. Some people don't feel enough in a half hour and eat a whole cookie and then another within 2 hours, and then by that time you have over done it and probably end up feeling sick and not enjoying it. I think in this case, you may have eaten two cookies right off the bat. Let it sink in for a few weeks and reevaluate it then. I know it took me a couple of months until I really enjoyed mine.
...but I want another cookie. :D Plus 2 bigger mufflers to quiet the beast. I have a trip to NC next weekend so I'll give it a whirl. 5 hours each way should give me sufficient time to let the exhaust soak in. If it's still painful after that point then throw on 2 big fat mufflers to mute this pig. We'll see and keep you posted. I'll try and post a vid to give you an idea of the sound. "I still want another cookie...please" :angel:
 

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Discussion Starter #7
One other observation. The car sounds close to an actual muffler delete. I've listened to mine and several others on youtube and they're almost identical. At cruising speeds it's tough to assess but at startup it's just obnoxious. We'll see...
 

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One other observation. The car sounds close to an actual muffler delete. I've listened to mine and several others on youtube and they're almost identical. At cruising speeds it's tough to assess but at startup it's just obnoxious. We'll see...
Just put on J pipes and it will sound quiet to you but not to everyone else....trust me it works

Sent with my carrier pigeon
 

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Discussion Starter #10
Easy fix just sent me your exhaust and I will sent you mine I want mine louder :)
Too late. Putting on Corsa w/catted DP. Selling my custom exhaust w/catless DP for $1199. Any takers?? Listed on www.e90post.com. E92, N55, VRSF DP.:thumbup:
 

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Discussion Starter #11
Just put on J pipes and it will sound quiet to you but not to everyone else....trust me it works

Sent with my carrier pigeon
My tech actually welding on 2 capped off resonators before the mufflers. It helped with the drone mostly but while cruising the engine/exhaust is a constant loud annoyance. I wanted it quiet in the cabin at higher speeds. Oh well live and learn. On to plan B...new exhaust ready tomorrow. :thumbup:
 

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My tech actually welding on 2 capped off resonators before the mufflers. It helped with the drone mostly but while cruising the engine/exhaust is a constant loud annoyance. I wanted it quiet in the cabin at higher speeds. Oh well live and learn. On to plan B...new exhaust ready tomorrow. :thumbup:
Did he measure the correct length? If not thats why you still have sound issues, from what you're telling me it sounds like they may be too short, do you have pictures of the ones he installed?
 

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Discussion Starter #13
Pics

Did he measure the correct length? If not thats why you still have sound issues, from what you're telling me it sounds like they may be too short, do you have pictures of the ones he installed?
Here you go...
 

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Here you go...
Hmm those don't look nearly long enough to get it to the level your expecting in terms of sound. There is a formula to calculating the length of pipe needed to cancel out the droning sound your hearing. The internal chamber might almost be the same volume but I think length if the pipe is the same diameter has more to do with the sound of the output. Similar to how woodwind instruments have similar sized holes as the output hole. But I could be wrong, my car went from drone so loud the cabin would be rattling and shaking to much less after using the formula. The J pipes need to be close to the same diameter as the exhaust pipe and be attached at an opening which is perpendicular to the flow of gas. So where he mounted them is correct I just think it's too short to get the intended result you're looking for.

For reference here are some mounted on a G8



And here is my car



Sent with my carrier pigeon
 
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